1. Field of the Invention
The invention relates generally to the equipment and methods used in the drilling and completion of wells. More specifically, the invention relates to advanced systems and methods for locating, activating, and managing downhole equipment.
2. Background Art
Hydrocarbons, such as oil and natural gas, are generally extracted from subsurface reservoirs by drilling a well that penetrates a targeted hydrocarbon-bearing formation. Once a wellbore has been drilled, the well must be “completed” before hydrocarbons can be produced. A completion process involves the design, selection, and installation of tubulars, tools, and other downhole equipment that are located in the wellbore for the purpose of conveying, pumping, and/or controlling the production of fluids (e.g., hydrocarbons) from the formation.
Each phase of well construction (e.g., drilling, completion, and production) includes using a variety of equipment, including tubular members such as casing, production tubing, landing nipples, and gas lift mandrels; flow control devices such as gas lift valves, subsurface safety valves, and packers; and other downhole equipment, such as perforating guns. In many situations it is necessary to lower one piece of equipment or a tool into the wellbore so that it can be installed at a particular location (e.g., at a selected depth and/or azimuthal position) in the wellbore. For example, a gas lift valve may be positioned in a selected gas lift mandrel, and there may be several gas lift mandrels disposed at different selected depths in the wellbore. Alternatively, a different well tool may be used to perform a desired action at a desired location in the wellbore (e.g., a perforating gun may be used to perforate well casing at a particular depth proximate a targeted hydrocarbon-bearing formation in the wellbore).
When drilling and completing a well, it is generally necessary to determine when a selected piece of downhole equipment is in a desired location in the wellbore. Prior methods for making this determination include, for example, lowering a tool into the wellbore on a wireline. However, positioning downhole tools in a wellbore “blindly” (e.g., by simply lowering a tool into the wellbore on the wireline or on a drillstring until it “lands” in an associated tool previously positioned in the wellbore) may be an imprecise operation. For example, a wireline retrievable subsurface safety valve can be lowered into a wellbore on a wireline to be installed in a particular landing nipple. If, for example, multiple landing nipples are located in the wellbore, the uppermost landing nipple generally must have a large inner diameter, and subsequent landing nipples positioned at increasing depths in the wellbore must have successively smaller inner diameters so that the valve may be placed at the desired depth in the well. This requires the use of multiple sizes (e.g., multiple decreasing inner diameters) of landing nipples, as well as correspondingly sized safety valves.
The multiplicity of sizes and/or diameters increases a required inventory and decreases interchangeability of tools. Moreover, the range of diameters that may be used in a selected wellbore will be limited by the drilled diameter of the wellbore and by a final production diameter required to allow sufficient flow from a bottom of the wellbore to the surface.
There is a need, therefore, for a system of and method for precisely positioning, activating, and orienting downhole tools at selected depths in the wellbore. Moreover, there is a need for a downhole system that can transmit instructions to downhole tools and that may be used with a variety of tool and wellbore sizes.